JPH0953721A - Reverse shift car speed restricting device for manual transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reverse shift car speed restricting device which restricts the shift from a neutral position to a reverse shift position which accomplishes back gear, when the car speed exceeds a set car speed. SOLUTION: A an axial mounting hole 12a which is open axially outward, is provided on the outside peripheral part of a synchro-hub 12, and a locking member 21 which is axially inward spring-energized, and is projected axially outward against spring-energizing when the car speed exceeds a set car speed, is assembled to the mounting hole 12a so that it can move axially. Further, corresponding to the locking member 21, a notch 13a which permits the entering- engagement of the locking member 21 into the inner periphery of a switching sleeve 13, permits axial movement of the switching sleeve 13 between a neutral position and a forward shift position F when it is engaged with the locking member 21, and restricts axial movement of the switching sleeve from the neutral position to a reverse shift position R, is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reverse shift vehicle speed limiting device for a manual transmission equipped in a vehicle, in which reverse shift is limited according to the vehicle speed.

[0002]

2. Description of the Related Art As one of manual transmissions, a switching sleeve axially movably mounted on the outer periphery of a synchronizing hub which rotates integrally with an output shaft is axially moved from a neutral position to a forward shift position. In some cases, the forward shift stage is completed by the above, and the reverse stage is completed by axially moving the switching sleeve from the neutral position to the reverse shift position. In such a manual transmission, there is a misshift prevention mechanism that prevents the switching sleeve from axially moving from the forward shift position to the reverse shift position beyond the neutral position (in other words, reverse shifts when the vehicle moves forward). One of them is provided in Japanese Patent Publication No. 54-23060.

[0003]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
The misshift prevention mechanism disclosed in Japanese Patent No. 23060 is incorporated in a shift operation mechanism provided between the shift lever and the switching sleeve, and the switching sleeve moves from the forward shift position (the fifth shift position) by operating the shift lever. It operates only when it is axially moved directly to the reverse shift position beyond the neutral position, and when the shift lever is shifted from the 5th gear shift position to the neutral position, it is operated to select and then to the reverse shift position. If the shift lever is shifted from the forward shift position other than the 5th speed to the neutral position and then the select operation is performed to shift to the reverse shift position, the misshift prevention mechanism does not function and the reverse shift position is lost. It has a structure that allows shift operation.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and is a switching sleeve mounted on the outer periphery of a synchronizing hub which rotates integrally with an output shaft so as to be movable in the axial direction. A manual shift that completes the forward gear by moving the switch from the neutral position to the forward shift position in the axial direction, and by moving the switching sleeve axially from the neutral position to the reverse shift position to complete the reverse position. In the machine, a radial mounting hole that opens radially outward is provided on the outer peripheral portion of the synchronizing hub, and the mounting hole is spring-biased radially inward to resist the spring bias when the vehicle speed is equal to or higher than a set vehicle speed. A locking member that projects radially outwardly so as to be movable in the radial direction, and allows the lock member to engage in the inner periphery of the switching sleeve in correspondence with the locking member. Further, a notch is provided to allow axial movement of the switching sleeve between the neutral position and the forward shift position when engaging with the lock member and to restrict axial movement from the neutral position to the reverse shift position. To do.

[0005]

In the reverse shift vehicle speed limiting device for the manual transmission according to the present invention, the rotation of the output shaft causes the lock member to receive the centrifugal force, and when the vehicle speed is equal to or higher than the set speed, the spring member resists the spring bias and is radially outward. Project to. At this time, if the switching sleeve is in the neutral position or the forward shift position, the lock member rush-engages with the notch of the switching sleeve. Therefore, the switching sleeve is allowed to move in the axial direction between the neutral position and the forward shift position, and is restricted from moving in the axial direction from the neutral position to the reverse shift position. Therefore, if the vehicle speed is equal to or higher than the set speed when the vehicle is running, the axial direction from the neutral position to the reverse shift position of the switching sleeve is axially changed by the lock member that is rush-engaged with the cutout of the switching sleeve regardless of any forward speed or neutral state. Movement is regulated and reverse misshift is reliably prevented.

Further, when the vehicle speed is less than the set vehicle speed, the lock member, which is spring-biased radially inward, is accommodated in the mounting hole of the synchro hub and is not engaged with the notch of the switching sleeve. The switching sleeve is allowed to move axially between the neutral position and the forward shift position, and is allowed to move axially between the neutral position and the reverse shift position.

Further, the switching sleeve functions as a stopper for restricting the outward movement of the lock member, so that the lock member is prevented from abnormally protruding outward at high vehicle speeds. In any case (for example, when traveling at high speed), an excessive load does not act on the spring biasing inward, and damage to the spring can be suppressed.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a part of a manual gear transmission mounted on a vehicle. In this transmission, a synchro hub 12 is attached to the outer periphery of an output shaft 11 so as to be capable of transmitting torque and immovable in the axial direction. The output shaft 11 and the synchro hub 12 are designed to rotate integrally,
A switching sleeve 13 is attached to the outer periphery of the synchro hub 12 so as to be able to transmit torque and move in the axial direction. As is well known, the switching sleeve 13 is axially moved by a shift operation of a shift lever (not shown) via a gear shift operation mechanism (not shown), and a forward shift from the neutral position shown to the right side shown in the figure. The forward shift stage (for example, the fifth speed) is completed by axially moving to the position F, and the reverse shift stage is completed by axially moving from the neutral position to the reverse shift position R on the left side in the drawing. Has become.

By the way, in this manual gear transmission, as shown in FIGS. 1 to 3, a lock member 21 is provided on the outer peripheral portion of the synchro hub 12 together with a spring 22 and a retainer 23 at equal intervals (120 degrees) in the circumferential direction. 3) and the notches 13a are provided on the inner circumference of the switching sleeve 13 in correspondence with these. Each lock member 21 is a pin having a substantially oval cross section that is long in the circumferential direction,
It is movably assembled in a radial mounting hole 12a provided on the outer peripheral portion of the synchro hub 12 and opening radially outward, and can be housed in the mounting hole 12a or project radially outward from the mounting hole 12a. And a stepped through hole 21a having a large diameter outward is provided in the shaft center portion.

Each spring 22 is a compression coil spring, and is incorporated in the large diameter portion of the stepped through hole 21a of the lock member 21 together with the retainer 23 to bias the lock member 21 and the retainer 23 away from each other. In the illustrated state, when the rotation of the output shaft 11 exceeds the set vehicle speed, the lock member 21 is radially outwardly compressed and deformed. Each retainer 23 is a hollow pin whose one end has a hemispherical shape, and the hemispherical end (where the communication hole 23a is provided) is radially outward, and the stepped through hole 21 of the lock member 21.
It is incorporated in the large-diameter portion of a so as to be movable in the radial direction, and slidably contacts the notch 13a of the switching sleeve 13 at the hemispherical end. Each notch 13 of the switching sleeve 13
a is provided in the axial direction from the center of the inner circumference of the switching sleeve 13 to the left end in FIGS.
The outer diameter end of No. 1 is formed into a shape capable of being rush-engaged,
When the radially outer end of the lock member 21 is thrust into engagement, the neutral position of the switching sleeve 13 and the forward shift position F
The axial movement between the neutral position and the reverse shift position R is restricted by allowing the axial movement between the neutral position and the reverse shift position R.

In this embodiment constructed as described above, the lock member 21 receives a centrifugal force due to the rotation of the output shaft 11 and projects outward in the radial direction against the biasing force of the spring 22 when the vehicle speed is equal to or higher than the set vehicle speed. . At this time, if the switching sleeve 13 is in the neutral position or the forward shift position, the lock member 21 is inserted into the notch 13a of the switching sleeve 13 as illustrated in the state where the switching sleeve 13 is in the neutral position in FIGS. Engage. Therefore, the switching sleeve 13 is allowed to move in the axial direction between the neutral position and the forward shift position, and is restricted from moving in the axial direction from the neutral position to the reverse shift position. Therefore, if the vehicle speed is equal to or higher than the set vehicle speed when the vehicle is running, the lock member 21 rush-engages with the cutout 13a of the switching sleeve 13 from any forward gear position or neutral state to shift the switching sleeve 13 from the neutral position to the reverse shift position. Axial movement is restricted and reverse misshift is reliably prevented.

On the other hand, when the vehicle speed is less than the set vehicle speed, the spring 22
The lock member 21 is biased inward by the
Is accommodated in the mounting hole 12a of the synchronizing hub 12 and is not engaged with the notch 13a of the switching sleeve 13, the switching sleeve 13 is allowed to move in the axial direction between the neutral position and the forward shift position, and at the same time, the neutral position. Is allowed to move in the axial direction between the reverse shift positions. It should be noted that in the state where the lock member 21 is housed in the mounting hole 12a of the synchronizing hub 12, the switching sleeve 1
3 is axially moved from the neutral position to the reverse shift position, the switching sleeve 13 retains the retainer 23.
Engaging the hemispherical end of the retainer 23 to move the retainer 23 radially inward against the spring 22 and when the switching sleeve 13 is axially moved from the reverse shift position to the neutral position. It is pushed radially outward by and is engaged with the cutout 13a of the switching sleeve 13 at the hemispherical end as shown in FIGS.

Further, in this embodiment, the switching sleeve 13 functions as a stopper for restricting the outward movement of the lock member 21, and the lock member 21 is prevented from abnormally protruding outward at high vehicle speed. To prevent this, the spring 22 that biases the lock member 21 radially inward does not receive an excessive load in any case (for example, during high-speed traveling), and the spring 2
The damage of 2 can be suppressed.

In the above embodiment, the lock member 21.
The spring (compression coil spring) 22 housed in the stepped through hole 21 of the lock member 21 together with the retainer 23 was used as a spring for urging the lock member 21 inwardly. As the stepped pin having a small diameter, a spring (compression coil spring) provided on the outer circumference of the small diameter portion of the stepped pin and engaged with the annular retainer provided on the synchronizing hub 12 and the stepped portion of the stepped pin is adopted. Alternatively, a spring (tension coil spring) that is incorporated in the inner diameter side of the through hole and engages with the lock member 21 and the annular retainer provided on the synchro hub 12 is used as the through hole. It is possible. Further, in the above-described embodiment, the lock member 21, the spring 22, the retainer 23, and the like are provided at three equal intervals in the circumferential direction, but the number can be increased or decreased as appropriate.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing an embodiment of a reverse shift vehicle speed limiting device for a manual transmission according to the present invention.

FIG. 2 is an enlarged sectional view of a main part of FIG.

FIG. 3 is a cross-sectional view taken along line 3-3 in FIG.

FIG. 4 is a diagram for explaining the operation of the main part of FIG.

FIG. 5 is a sectional view taken along line 5-5 in FIG. 4;

[Explanation of symbols]

11 ... Output shaft, 12 ... Synchro hub, 12a ... Mounting hole,
13 ... Switching sleeve, 13a ... Notch, 21 ... Lock member, 22 ... Spring, 23 ... Retainer.

Claims (1)

[Claims] 1. A forward shift stage is completed by axially moving from a neutral position to a forward shift position a switching sleeve mounted axially movably on the outer periphery of a synchro hub that rotates integrally with an output shaft. Further, in a manual transmission in which the reverse gear is completed by axially moving the switching sleeve from the neutral position to the reverse shift position, a radial mounting hole is formed on the outer peripheral portion of the synchronizing hub in a radially outward direction. And a lock member that is spring-biased radially inwardly in this mounting hole and that projects radially outwardly against the spring bias when the vehicle speed is equal to or higher than the set vehicle speed, Corresponding to the lock member, the inward engagement of the lock member is permitted on the inner circumference of the switch sleeve, and the neutral position and the flap of the switch sleeve are engaged at the time of engagement with the lock member. A reverse shift vehicle speed limiting device for a manual transmission, which is provided with a notch that allows axial movement between forward shift positions and restricts axial movement from a neutral position to a reverse shift position.